Implemented desktop notifications!
Added windows startmenu shortcut creation

This is required since windows8 for showing toast notifications.
Added notification indicators

* The titlebar auth button now shows if notifications are enabled.
* The user.index route also does
* Changed some computed properties from alias to readOnly
Fixed return value of utils/download
Implemented a generic denodify function
Implemented an icon cache garbage collection

Icons older than 7 days will now be removed from the cache folder.
Made the notification text a bit more clear
Hide notification click settings from linux users

Node-webkit doesn't support notification click events on linux...
Merge branch 'notifications'

* Implemented desktop notifications!
* Added windows startmenu shortcut creation
  This is required since windows8 for showing toast notifications.
* Added notification indicators
  * The titlebar auth button now shows if notifications are enabled.
  * The user.index route also does
  * Changed some computed properties from alias to readOnly